Former San Diego Chargers and Dallas Cowboys quarterback Ryan Leaf was moved out of a drug treatment center in Montana and into the state prison.

Dawn Handa, a regional probation and parole administrator, told the Great Falls Tribune on Thursday that Leaf was taken out of the Nexus Treatment Center in Lewistown after violating the conditions of the placement, including threatening a staff member. He was transferred to the state prison in Deer Lodge.Leaf pleaded guilty to burglary and criminal possession of dangerous drugs after being charged with breaking into two houses and stealing prescription painkillers. He was sentenced to five years with the Department of Corrections in June with the recommendation that he spend the first nine months of the sentence in a locked drug treatment center.He may also have a 10-year probationary sentence for a 2010 drug and burglary conviction in Texas revoked.